This invention pertains to bicycle wheels having pneumatic tires, inner tubes, rims, spokes and nipples, and a flexible rim strip. In such wheels, the spoke nipples are inserted through holes in the rim, and engage the threaded outward ends of the spokes.
In the past, inside the rim, a flexible rim strip has lain over the heads of the spoke nipples, to protect the inner tube from the rough nipple heads. The circular rim strip has had a hole in it for the valve stem to pass through. The circular rim strips have been made by joining together the free ends of a strip of rubber with adhesive, and punching a hole for the valve stem, usually in the area of double thickness.
During recent years, tires having smaller cross sections have become popular, along with correspondingly narrow rims, resulting in a crowded situation at the valve stem. Almost no room has been left for the rim strip on either side of the valve stem. The narrow rim strips have been almost cut in two by their valve stem holes, and have been prone to breaking because of it.
In addition, the tube valve stem is often coated with rubber, causing friction between it and the rubber rim strip, making mounting and dismounting of the tire difficult.